S
M
T
W
T
F
S
30
80°
52°
31
76°
66°
1
77°
66°
2
73°
65°
3
83°
70°
4
84°
63°
5
79°
59°
6
70°
53°
7
79°
54°
8
81°
62°
9
79°
70°
10
82°
65°
11
77°
55°
12
75°
62°
13
79°
61°
14
80°
60°
15
78°
58°
16
74°
55°
17
72°
56°
18
72°
57°
19
72°
51°
20
75°
55°
21
74°
56°
22
67°
56°
23
67°
55°
24
68°
55°
25
69°
53°
26
71°
54°
27
67°
49°
28
67°
54°
29
72°
54°
30
73°
53°
1
73°
54°
2
72°
54°
3
71°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Westhampton Beach
Westhampton Beach's September 2026 forecast shows daily high temperatures ranging from 67° to 82°, with overnight lows between 49° and 70°. The average high for September is 73° with an average low of 56°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Westhampton Beach. See also: October | November | December.